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Common reed grass (Phragmites) is a tall, invasive perennial wetland grass ranging in height from 3-15 feet. The plant produces horizontal rhizomes that grow on or beneath the ground and produce roots and vertical stalks. The rhizomes allow the plant to form large colonies. The stiff, hollow stalks support leaf blades that are smooth, broad and flat (1-1/2 - 2 inches wide).

Mechanical Control

Phragmites can be cut down or the rhizomes (roots) can be dug up. It will be difficult to control this way because it will regrow from seeds and remaining rhizomes.

Chemical Control

Systemic herbicides, such as Shoreline Defense®, will work to kill the root of the plant.

Chemical Application Best Practices

Anytime you use chemicals treat weeds or algae, please keep in mind the following:

  • Treat your pond in sections. Treat only half the pond's surface at a time, if the weather is hot, only treat 1/4-1/3 of your pond. Wait 10-14 days between treatments.
  • Once the weeds have browned, use a Weed Cutter to remove as much dead material as possible. This prevents an accumulation of dead plant material and muck.
  • Treat your pond with the proactive approach to pond management. Use PondClear™, MuckAway™ and Pond Dye to keep your pond looking great.